Container closure



July 3, 1934. G. LANGE CONTAINER CLOSURE Filed Oct. 22, 19250 DQQQ ATTORN EYS Patented July 3, 1934 PATENT OFFICE CONTAINER CLOSURE Louvern G. Lange, Passaic, N. J.

Application October 22,

3 Claims.

This invention relates to container closures and more particularly to a material especially suitable for making inserts or liners for bottle caps, jar covers and the like. My invention also comprises an improved method of making such insert or liner material.

It has been common practice in the past to provide metal bottle caps, jar covers and the like with cork inserts which come directly in contact with the top of the bottle, or other receptacle. These cork inserts or discs are clamped in position by any suitable means, such as the crimped edge of the ordinary bottle cap, and the insert is supposed to form a seal for the contents of the container. The use of natural cork for this purpose is not very satisfactory because the natural cork contains imperfections which may render an insert made from this material incapable of forming a complete seal for the container. Composition cork inserts have been employed, such inserts comprising comminuted cork and a suitable binder. Such composition inserts, or liners, are more dense and uniform than such liners made from the natural product but they are still unsatisfactory for many purposes because of the fact that the binder of the composition is attacked by many solvents and this results in disintegration of the material which is supposed to form the seal for the container.

It has also been proposed to use a'resilient material such as paper felt, or the `like, which provides the necessary iiexibility or resiliency, this material being covered by a layer of varnished paper, or other non-absorbent material impervious to moisture. Where such composite inserts or liners are employed, reliance is placed mainly on the varnished paper, or the like, to provide the necessary seal, for the underlying resilient material is quite porous and incapable of forming a The present invention relates to an improved material suitable for bottle cap liners. a material which possesses the requisite resiliency and which is capable of forming an hermetic seal, the composition of the material being such that it is not affected by ordinary solvents or by acids, such as acetic acid, carbonio acid and the like which are often present in the contents of sealed bottles and jars. In general my invention is based on the discovery that resilient, fibrous material, such as pulp board, news board, white or gray felt, can be so treated as to render it impervious to liquids and gases, whereby it may be used as a liner for bottle caps, jar covers and the like without the necessity of employing any covering layer 1930, Serial N0. 490,421

of varnished paper or the like. Material such as pulp board, news board, or paper felt, is ordinarily highly absorbent and it is so porous that it would ordinarily be regarded as wholly unsuited to the purpose of providing a water and gas tight seal without being covered with varnished paper, or` other impervious material. I have discovered however that if such brous resilient material is i treated with a composition such as that hereinafter described the resulting product is capable 55 of forming a perfect seal, at least when under compression as is ordinarily the case with bottle cap liners. The material is preferably, although not necessarily, completely impregnated with the said composition and the use of this product has demonstrated its value as an insert or liner for bottle caps, jar covers and the like! In general my invention involves the use of resin and nitrocellulose, these materials being combined in solution to produce a liquid with which fibrous material may be impregnated. The resin' and nitrocellulose are each dissolved in a suitable solvent, a plasticizer is added to the nitrocellulose, and then the resin solution is added to the resulting mixture. The plasticizer may com- 8 prise a drying oil, such as heavy body linseed oil, or China-wood oil, or the like, and in some cases where a more pliable impregnated product is desired a non-drying oil may be employed, such as heavy blown rape seed oil, or castor oil. In general, by a nondrying oil I have reference to such non-drying oils as are familiar to the paint and varnish industry.

I prefer to incorporate raw rubber such as crepe rubber in the impregnating composition to add resilience. The rubber may be dissolved in any of the usual solvents, such as benzol or toluol and this rubber solution may be added to the mixture of dissolved nitrocellulose and oil. Like the oil, the rubber serves as a plasticizer and it adds resilience vto the impregnated product. The useof rubber is not essential in all cases, however, particularly where the resulting composition need not be especially resilient or pliable. Y

I prefer to employ Cumar resin, but it is to be understood that other resins and in particular the common natural resins may be employed to advantage, although my experience indicatesV that Cumar resin gives the best results. The resin may be cut down in the usual diluents such as benzol, toluol and the like, and where the raw rubber is employed this ingredient may be dissolved in such ordinary solvents as benzol or toluol. 110

After the nitrocellulose solution has been prepared as indicated above the oil, or other plasticizer, may be added and thereafter the solutions of rubber and resin are combined with the mixture of dissolved nitrocellulose and oil.

The liquid composition when used for the purpose of impregnating materials such as news board, pulp board, or felt, may have the consistency of thick syrup. The impregnation process can be conveniently carried out by immersing the material to be impregnated in the liquid composition and subjecting the material tol "repeated compression or squeezing while submerged in the liquid. The excess liquid adhering to the surface of the material can be removed in any desired manner and the impregnated material can be dried, preferably at a temperature in the neighborhood of 160 degrees Fahrenheit for 15 to 20 minutes to drive off the volatile solvent. The impregnation process can be facilitated by maintaining the bath of liquid at a temperature somewhat above atmospheric temperature.

The various objects and advantages of my invention will be more apparent upon considering the following detailed description which is to be taken in conjunction with the accompanying drawing in which Fig. 1 is a vertical section view of apparatus suitable for use in making my improved product;

Fig. 2 is a plan view of a strip of material embodying my invention;

Fig. 3 is an enlarged section view of a portion of the product illustrated in Fig. 2;

Fig. 4 is a plan view of a strip of material made in accordance with my invention and having varnished paper, or the like, bonded thereto;

Fig. 5 is an enlarged view of a disc or bottle cap insert made of the material illustrated in Fis. 4;

Fig. 6 is a transverse section view of the material shown in Fig. 5;

Fig. 7 is an enlarged fragmentary section view of the products shown in Figs. 4, 5 and 6;

Fig. 8 is a plan view of a bottle cap embodying my invention and Fig. 9 is a vertical section view of the neck of a. bottle having applied thereto a bottle cap made in accordance with my invention.

Referring to4 the accompanying drawing I have illustrated in Fig. 1 thereof a bath or tank l having a jacket 2 surrounding the same and providing an intermediate space for a heating medium such as hot water, steam, or the like, which may be admitted to the jacketed space through an inlet 3 and discharged through an outlet 4. 'I'he tank l is adapted to contain a quantity of the impregnating composition, the surface of this impregnating bath being represented by the reference character 5. This impregnating composition as previously explained comprises resin and nitrocellulose dissolved in suitable solvents and mixed with a plasticizer which may include a drying oil or a non-drying oil and it may also include raw rubber dissolved in a suitable solvent. The following exampleindicates the suitable proportions of the various ingredients expressed as parts by weight of the dried residue of the impregnating composition. Parts Resin, preferably Cumar resin 15 Nitrocellulose 35 Oil, preferably heavy body linseed oil, rape seed oil, or the like 35 Raw rubber T 15 In the example given above the amount of oil can be varied between 35 parts to 40 parts, depending upon the character of the finished product desired. The relative proportions of the other ingredients may likewise be varied to alter the characteristics of the composition, as may be desired, and in general, satisfactory results can be obtained by varying the relative proportions as indicated below:-

10 to 2O parts resin 30 to 40 parts nitrocellulosev 30 to 40 parts oil 10 to 20 parts raw rubber It will be understood that the solutions of nitrocellulose, oil, resin and rubber are so combined as to produce a composition, the dried residue of which contains the ingredients in the proportions by weight as indicated above.

The tank illustrated in Fig. 1 is equipped with a plurality of pairs of squeeze rolls 6, 7, 8 and 9 which are normally submerged in the bath of impregnating composition in the tank. A strip of fibrous material 10 such as pulp board, news board, or gray felt, is passed between the squeeze rolls and it will be understood that during this operation the strip of material is submerged in the bath of impregnating composition and successively subjected to a squeezing action which serves to force the impregnating composition into the interstices of the fibrous material. The upper squeeze rolls ar not necessarily completely submerged in the bath but the level of the impregnating composition should be high enough to cover the strip of fibrous material advancing,

through the apparatus. As the impregnated material leaves the bath it passes between a pair of rollers 11 which remove excess impregnating composition from the surfaces of the strip. The strip of material after passing through the impregnating apparatus is then dried preferably at a temperature in the neighborhood of 160 F. from 15 to 20 minutes to drive off the volatile solvent. It will be understood that the impregnating composition in the tank 1 is preferably viscous and its viscosity may be regulated by regulating the temperature of the bath. The squeeze rolls serve to work the impregnating composition into the sheet of fibrous material, the action -being similar to that of repeatedly compressing a sponge beneath the surface of a liquid whereby the liquid is drawn into the interstices of the porous body.

Figs. 2 and 3 represent the finished impregnated strip, Fig. 2 showing circular discs cut out of the strip as indicated at 12 preparatory to inserting the same into bottle caps or jar covers. This material, due to its impregnation with the composition above described, is capable of forming an air tight seal and the ingredients of the impregnating composition are such that they are inert to ordinary acids such as acetic acid, carbonic acid, as well as to such agents as alcohol and the like. The product is pliable and resilient and is therefore capable of conforming with the contour of a bottle cap, or the top of a jar when subjected to ordinary pressure.

Figs. 8 and 9 show the material of Figs. 2 and and 3 applied to an ordinary bottle cap consisting of a cup-shaped metal cap 13 having a crimped edge 14 adapted to fit over the top of the bottle. This metal cap is provided with a liner or insert 16 the edge portion of which engages the upper end of the neck of the bottle to form a seal.

As'explained above my improved insert or liner material is of itself capable of forming a perfect hermetic seal without the necessity of employing any covering material such as varnished paper, or the like. It will be understood however that the use of such covering material may be desirable in some cases, for example, where the cover or cap is to be repeatedly applied to and removed from the container in which event continuous use might injure the'liner material. For such purposes and in fact in every case where it is desirable to provide such a. protective layer varnished paper may be applied to the impregnated material and I have illustrated this use of the invention in Figs. 4 to 'l inclusive. Fig. 4 illustrates a strip of the impregnated material. 17 having a layer of varnished paper 18 bonded thereto by any suitable adhesive. While any ordinary adhesive may be employed I prefer to use gutta percha. The outer surface of the covering layer of paper is coated with a varnnish which is preferably insoluble in alcohol, acetic acid, carbonic acid and the like. In the enlarged view of Fig. '7 the covering layer of paper is illustrated at 19, the coating of varnish at 20 and reference character 21 designates the adhesive whichserves to bond the paper to the underlying impregnated material 17.

Iclaim: 1. An article of manufacture comprising a pliable sheet of fibrous material and the dried residue of a composition comprising resin, nitrocellulose, a drying oil and raw rubber, the rela,- tive proportions by Weight of the ingredients of said dried composition being 10 to 20 parts resin, 30 to 40 parts nitrocellulose, 30 to 40 parts oil, and 10 to 20 parts rubber.

2. An article of manufacture comprising a pliable sheet of fibrous material and the dried residue of a composition comprising resin, nitrocellulose, a drying oil and raw rubber, the relative proportions by weight of the ingredients of said dried composition being approximately 15 partsresirr, 35 parts nitrocellulose, 35 to 40 parts oil and 15 parts rubber.

3. An article of manufacture comprisng a pliable sheet of fibrous material and the dried residue of a composition comprising resin, nitrocellulose, a drying oil and raw rubber, `the relative proportions by weight of the ingredients o! said dried composition being approximately 15 parts resin, 35 parts nitrocellulose, 35 parts oil and 15 parts rubber.

LOUVERN G. LANGE. 

